As the Nobel Peace Prize ceremony for Chinese dissident Liu Xiaobo inches closer, Chinese authorities are continuing to harass Liu’s supporters and other critics of the government. The latest dissident writer to suffer harassment at the hands of Chinese police is Zhang Heci, an Australian citizen, who was travelling to Norway via China to attend the ceremony being held for Liu Xiaobo.

According to media reports, Mr. Zhang said that police boarded his plane after it landed in Shanghai and escorted him to an interrogation room where he was searched and prevented from calling his wife in Australia. He was held for 24 hours.

Zhang says Chinese authorities have forced him to return to Australia, but not before engaging in “torturous mistreatment of me,” he wrote in an open letter to Australian Foreign Minister Kevin Rudd.

Four policemen are reported to have guarded the room where Zhang slept and watched him use the toilet, “apparently enjoying the pleasure of humiliating me.”

“They have no right to cut off my journey to Oslo to attend Liu Xiaobo’s ceremony.”

Zhang is a Melbourne-based writer known for his comments on human rights. He is also the grandson of noted philosopher and former political activist Zhang Dongsun—who suffered censorship and persecution by Mao for his advocacy of democratic government. Dai Qing, another noted dissident writer, recently published a book about Zhang Dongsun’s life called “In the Palm of the Buddha: The Life and Times of Zhang Dongsun” and delivered the Australian National University’s 2007 Morrison Lecture [PDF] on the man’s important contribution to Chinese political philosophy.

The younger Mr. Zhang’s harassment comes amidst a much larger crackdown on critics. According to a spokesman for Amnesty, 272 people have been locked up to either prevent them attending the ceremony or voicing their support for Liu Xiaobo.

The list of those being harassed by Chinese authorities include, Ai Weiwei, one of the country’s most famous artists who was recently blocked from boarding a flight to South Korea. Other notable figures such as economist Mao Yushi and lawyer Mo Shaoping have also been prevented from leaving the country.

Dai Qing, meanwhile, has also been told by authorities not to attend any meetings or meet with foreign journalists.